vhost: introduce API to start a specific driver

[dpdk.git] / lib / librte_vhost / rte_virtio_net.h

diff --git a/lib/librte_vhost/rte_virtio_net.h b/lib/librte_vhost/rte_virtio_net.h
index d8e125d..fd9cbb0 100644 (file)
--- a/lib/librte_vhost/rte_virtio_net.h
+++ b/lib/librte_vhost/rte_virtio_net.h
@@ -87,13 +87,21 @@ struct rte_vhost_vring {
 /**
  * Device and vring operations.
  */
-struct virtio_net_device_ops {
+struct vhost_device_ops {
        int (*new_device)(int vid);             /**< Add device. */
        void (*destroy_device)(int vid);        /**< Remove device. */
 
        int (*vring_state_changed)(int vid, uint16_t queue_id, int enable);     /**< triggered when a vring is enabled or disabled */
 
-       void *reserved[5]; /**< Reserved for future extension */
+       /**
+        * Features could be changed after the feature negotiation.
+        * For example, VHOST_F_LOG_ALL will be set/cleared at the
+        * start/end of live migration, respectively. This callback
+        * is used to inform the application on such change.
+        */
+       int (*features_changed)(int vid, uint64_t features);
+
+       void *reserved[4]; /**< Reserved for future extension */
 };
 
 /**
@@ -124,6 +132,49 @@ rte_vhost_gpa_to_vva(struct rte_vhost_memory *mem, uint64_t gpa)
        return 0;
 }
 
+#define RTE_VHOST_NEED_LOG(features)   ((features) & (1ULL << VHOST_F_LOG_ALL))
+
+/**
+ * Log the memory write start with given address.
+ *
+ * This function only need be invoked when the live migration starts.
+ * Therefore, we won't need call it at all in the most of time. For
+ * making the performance impact be minimum, it's suggested to do a
+ * check before calling it:
+ *
+ *        if (unlikely(RTE_VHOST_NEED_LOG(features)))
+ *                rte_vhost_log_write(vid, addr, len);
+ *
+ * @param vid
+ *  vhost device ID
+ * @param addr
+ *  the starting address for write
+ * @param len
+ *  the length to write
+ */
+void rte_vhost_log_write(int vid, uint64_t addr, uint64_t len);
+
+/**
+ * Log the used ring update start at given offset.
+ *
+ * Same as rte_vhost_log_write, it's suggested to do a check before
+ * calling it:
+ *
+ *        if (unlikely(RTE_VHOST_NEED_LOG(features)))
+ *                rte_vhost_log_used_vring(vid, vring_idx, offset, len);
+ *
+ * @param vid
+ *  vhost device ID
+ * @param vring_idx
+ *  the vring index
+ * @param offset
+ *  the offset inside the used ring
+ * @param len
+ *  the length to write
+ */
+void rte_vhost_log_used_vring(int vid, uint16_t vring_idx,
+                             uint64_t offset, uint64_t len);
+
 int rte_vhost_enable_guest_notification(int vid, uint16_t queue_id, int enable);
 
 /**
@@ -204,9 +255,20 @@ int rte_vhost_get_negotiated_features(int vid, uint64_t *features);
 
 /* Register callbacks. */
 int rte_vhost_driver_callback_register(const char *path,
-       struct virtio_net_device_ops const * const ops);
-/* Start vhost driver session blocking loop. */
-int rte_vhost_driver_session_start(void);
+       struct vhost_device_ops const * const ops);
+
+/**
+ *
+ * Start the vhost-user driver.
+ *
+ * This function triggers the vhost-user negotiation.
+ *
+ * @param path
+ *  The vhost-user socket file path
+ * @return
+ *  0 on success, -1 on failure
+ */
+int rte_vhost_driver_start(const char *path);
 
 /**
  * Get the MTU value of the device if set in QEMU.
@@ -228,7 +290,7 @@ int rte_vhost_get_mtu(int vid, uint16_t *mtu);
  * is allocated.
  *
  * @param vid
- *  virtio-net device ID
+ *  vhost device ID
  *
  * @return
  *  The numa node, -1 on failure
@@ -240,11 +302,11 @@ int rte_vhost_get_numa_node(int vid);
  * Get the number of queues the device supports.
  *
  * Note this function is deprecated, as it returns a queue pair number,
- * which is virtio-net specific. Instead, rte_vhost_get_vring_num should
+ * which is vhost specific. Instead, rte_vhost_get_vring_num should
  * be used.
  *
  * @param vid
- *  virtio-net device ID
+ *  vhost device ID
  *
  * @return
  *  The number of queues, 0 on failure
@@ -268,7 +330,7 @@ uint16_t rte_vhost_get_vring_num(int vid);
  * file path.
  *
  * @param vid
- *  virtio-net device ID
+ *  vhost device ID
  * @param buf
  *  The buffer to stored the queried ifname
  * @param len
@@ -283,7 +345,7 @@ int rte_vhost_get_ifname(int vid, char *buf, size_t len);
  * Get how many avail entries are left in the queue
  *
  * @param vid
- *  virtio-net device ID
+ *  vhost device ID
  * @param queue_id
  *  virtio queue index
  *
@@ -298,7 +360,7 @@ uint16_t rte_vhost_avail_entries(int vid, uint16_t queue_id);
  * count is returned to indicate the number of packets that were succesfully
  * added to the RX queue.
  * @param vid
- *  virtio-net device ID
+ *  vhost device ID
  * @param queue_id
  *  virtio queue index in mq case
  * @param pkts
@@ -316,7 +378,7 @@ uint16_t rte_vhost_enqueue_burst(int vid, uint16_t queue_id,
  * construct host mbufs, copies guest buffer content to host mbufs and
  * store them in pkts to be processed.
  * @param vid
- *  virtio-net device
+ *  vhost device ID
  * @param queue_id
  *  virtio queue index in mq case
  * @param mbuf_pool